CVE-2025-68617
FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From versions 2.5.0 to before 2.5.2, a race condition during unloading of a DLS file can trigger a heap-based use-after-free. A concurrently running thread may be pending to unload a DLS file, leading to use of freed memory, if the synthesizer is being concurrently destroyed, or samples of the (unloaded) DLS file are concurrently used to synthesize audio. This issue has been patched in version 2.5.2. The problem will not occur, when explicitly unloading a DLS file (before synth destruction), provided that at the time of unloading, no samples of the respective file are used by active voices. The problem will not occur in versions of FluidSynth that have been compiled without native DLS support.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
- Puntuación base: 7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.21%
- Percentil entre todas las CVEs puntuadas: 11
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1203Exploitation for Client Executionexecution75 % - Impacto principal
T1499.004Application or System Exploitationimpact65 %
Requiere interacción del usuario (UI:R) para desencadenar la condición de carrera. La consecuencia es un crash/DoS por use-after-free en aplicación del cliente (FluidSynth sintetizador).
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-416
Referencias
- https://github.com/FluidSynth/fluidsynth/commit/685e54cdc44911ace31774260bd0c9ec89887491
- https://github.com/FluidSynth/fluidsynth/commit/962b9946b5cb6b16f0c08b89dd1b7016d4fce886
- https://github.com/FluidSynth/fluidsynth/issues/1717
- https://github.com/FluidSynth/fluidsynth/issues/1728
- https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-ffw2-xvvp-39ch
- https://github.com/FluidSynth/fluidsynth/issues/1717
- https://github.com/FluidSynth/fluidsynth/issues/1728
JSON original (NVD)
Mostrar
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